Don't track current field of state machines #2979
Merged
+34
−15
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Fixes the performance issue tested in #2977.
The problem was that we were tracking all possible returned values throughout the method, since we were treating them the same as hoisted locals. I'm sure it's still possible to come up with testcases that show bad performance (for example assigning many arrays to a hoisted local in the same iterator), but this should at least fix the immediate issue encountered in runtime.